It feels good: Harvard researchers have found that talking about yourself activates the same brain regions as sex, cocaine, and a good meal.

"Activation of this system when discussing the self suggests that self-disclosure like other more traditionally recognized stimuli, may be inherently pleasurable," Scientific American reports, "and that people may be motivated to talk about themselves more than other topics."

Esquire's Tom Chiarella perfectly captures how to make a great first impression. He writes:

On the street, in the lobby, square your shoulders to people you meet. Make a handshake matter — eye contact, good grip, elbow erring toward a right angle. Do not pump the hand, unless the other person is insistent on just that. Then pump the hell out of their hand. Smile. If you can't smile, you can't be gracious. You aren't some dopey English butler. You are you.

Why is this important? Because paying full attention to someone is a way of showing respect, and social science confirms that we get respect when we give respect. Add that to the list of reasons that conscientiousness predicts success.

3. Keep your posture open and upright.

Posture can influence the way others see you and the way you feel. Researchers have found that keeping your shoulders open and arms wide — a classic power pose — activates your hormone system in a way that makes you feel and look more confident and capable.

The same logic carries over to the way you sit. If you're scrunched over your laptop, you won't feel very bold, but if you're sitting at a large desk, you'll feel more assertive.

"Ignorance is one of the professional world's least respectable traits — if not the worst," Roberto Rocha writes at AskMen. "If you want your ideas to count, be better informed than everyone else."

So if you have a big pitch or meeting coming up, know exactly what message you want to communicate. Anticipate the objections your boss could have to whatever it is you're pitching. Not only will your ideas be stronger but you'll feel more confident presenting them.

5. Know what's going on in the world.

"Be up to speed on changes in your industry so you can speak about them intelligently," says Roberta Matuson. The "Suddenly in Charge" author recommends reading business news daily "so you can speak intelligently on business matters."

Further, strategic-marketing consultant Noah Fleming encourages a wider information diet by keeping up with tech, sports, and pop culture. (To hack your reading habits, read this.) The idea is to have a broad foundation of knowledge to draw from.

"You should be able to discuss, debate, and offer opinion across a number of different areas," Fleming says. "Serious people have strong opinions! You're taken seriously when you have and offer your opinions."

"You need enough self-confidence to command the respect of others, but that needs to be counter-balanced with knowing that there is much you simply don't know," he writes. "Humility is the path towards earning respect, while self-confidence is the path towards commanding it."

With that balance comes not only respect, he says, but also intellectual curiosity and optimism.

7. Don't let verbal tics undermine your authority.

If you say a statement with the intonation of a question, that's called "upspeak." It happens when you end your sentences with a higher pitch than they began with and makes you sound as if you're unsure of what you're saying.

In a recent survey, 85% of 700 professionals said upspeak is a sign of insecurity, while 57% think that upspeak makes people sound less credible.

"The numbers speak for themselves," says strategy consultant Bernard Marr. "Upspeak has no place at work. If you would like a thriving career, then simply don't do it!"